As far as I know the hitch heads are all rated for 1400/14000 but check the bars, they may not be. Some owners change them out for lighter ones. My friend picked a used one up which came with 1k bars.
As for the hitch itself, not much can go wrong with them other than regular wear and tear. The sleeves and bearings can get worn out but they are all replaceable. You can pull the caps off to check if the grease is clean etc but it's not easy to do. Hensley sells a refurb kit if you need. They will also send all new stickers if you want to repaint it.